摘要
天津六纬路城市广场采用了直径为1m,桩端埋深94m的大直径超长灌注桩,通过现场试验验证承载力取值及成桩可行性,试桩荷载试验加载至极限,为研究天津软土地区大直径超长灌注桩承载力特性及荷载传递机理提供了有价值的数据。本文以软土地区超长钻孔灌注桩为研究对象,进行超长桩的竖向抗压静荷载试验。试验结果表明:超长桩的荷载位移曲线为平缓型,属于典型的端承摩擦型桩曲线。桩身轴力的传递是自上而下进行的,即随着深度的增加轴力逐渐减小;桩身所承受荷载大部分由桩侧摩阻力提供,且由于地基土层性质的差异,桩侧摩阻力表现为随深度的“驼峰形”分布,当荷载达到一定值后,桩侧摩阻力不增反减,发生桩土软化的现象。
In Tianjin Liuwei Road City Square, large-diameter and super-long cast-in-place piles with a diameter of 1 m and a pile tip buried depth of 94 m are adopted. The value of bearing capacity and the feasibility of pile formation are verified by field tests, and the test pile load test is loaded to the limit. It provides valuable data for studying the bearing capacity and load transfer mechanism of large diameter and super-long cast-in-place piles in soft soil area of Tianjin. In this paper, super-long bored pile in soft soil area is taken as the research object, vertical compressive static load tests of super-long piles are carried out. The test results show that: the load displacement curve of super-long pile is gentle, it is a typical end-bearing friction pile curve. The pile axial force is transitte from top to bottom, that is, the axial force gradually decreases with the increase of depth. Most of the load borne by the pile is provided by the pile lateral friction, and due to the difference in the nature of soil layer, the pile lateral friction presents a “hump-shaped” distribution with depth. When the load reaches a certain value, the pile lateral friction resistance does not increase but decreases, and the phenomenon of pile-soil softening occurs.
作者
李甜甜
韩玉涛
刘永超
袁振宇
Li Tiantian;Han Yutao;Liu Yongchao;Yuan Zhenyu(Beijing Jiaotong Vocational Technical College,Beijing 102200,China;Tianjin University School of Civil Engineering,Tianjin 300350,China;Tianjin Jiancheng Development Group Co.Ltd,Tianjin 300301,China)
出处
《建筑科学》
CSCD
北大核心
2022年第3期90-96,共7页
Building Science
关键词
超长桩
软土
端承摩擦桩
桩侧摩阻力
overlength pile
weak soil
end bearing friction pile
pile lateral friction resistance
